Marble is a metamorphic rock formed by the recrystallization of sedimentary rocks, such as limestone or dolostone. Metamorphic rock is created by the Earth’s internal forces, including temperature, pressure and plate tectonics. Marble is formed when it is chemically or physically modified by any of these forces. When limestone is transformed, it is transformed into a denser and more compacted rock structure. Marble can be found throughout the world, and in diverse types, textures and colors. Because marble can be easily sculpted, it has found many uses in the construction of buildings and monuments, as well as an ornamental feature in house interiors.
Metamorphism
The forces involved in metamorphism (pressure, temperature, and plate tectonics) contribute to transform ingenuous and sedimentary rocks into more dense and compacted rock formations. Marble is formed by the mineral deposits of carbonate rocks, such as limestone and dolostone, into existing rock layers or by filling the rock fractures of these two types of rocks due to the extreme temperatures and pressures present in metamorphism, as well as the stresses occurring within the Earth’s crust and mantle. The result is a new orderly arrangement of the atoms, molecules and ions, which give a new form to a rock, modifying its structure.
Marble types
Pure marble is the product of very pure limestone or dolostone protolith, whereas other marble types with different textures and surface characteristics are due to mineral impurities, including sand, clay, silt and iron oxides, originally present in limestone. There are many marble types each with distinct surface characteristics, texture and color, including the Creole, Carrara, Parian, Yule, Vermont, Pentelic and Etowah marbles, among many others. Due to its physical characteristics, including softness, resistance to shattering and waxy appearance, marble has been used for a large number of useful purposes.
How it is used
Pure marble stone can be easily sculpted, thus, it has been used in the creation of buildings and statues for centuries. Some marble types have been widely used since ancient times. Carrara marble utilization can be trace back to ancient Rome, for example the Pantheon and Trajan’s Column are made of this type of marble. Many sculptures of the 1500’s were made using Carrara marble. One of the most outstanding is the statue of David created by Michelangelo. Creole marble has been extensively used in the construction of monuments and buildings in the United States. Many masterpieces in ancient Greece were sculptured using Parian marble.
Yule marble is almost exclusively found only in the Yule Creek Valley in Colorado. Yule marble is an almost 100% pure calcite type with a homogeneous look, smooth texture and bright surface. Yule marble was used to construct the exterior of the Lincoln memorial in Washington, D.C., and many other buildings throughout the United States. Penteli marble was used in the construction of Acropolis in ancient Athens. Etowah marble is a peculiar type of marble with a salmon pink color. The physical characteristics of this type of marble make it functional for house interior decoration applications.
Marble has been one of the most preferred materials in the construction of buildings and sculpture of monuments since very ancient times. Marble has been used by artists to create renowned sculptures since the classical period and throughout the renaissance. In the present, marble can be seen utilized as an ornament in buildings and houses. Marble production in the U.S. is at approximately 50,000 tons a year, and the production of Pakistan, the largest exporter, totals 100,000 tons per year. According to hu.edu.jo, the high production of marble is associated with the adverse impact on the environment caused by a considerable quantity of waste materials; therefore, the ornamental manufacture industry requires a mitigation process and environmental assessment to minimize the negative impact that it may produce on the environment.
